US4709104A - Crystallization-inhibited trimethylolethane solutions - Google Patents

Crystallization-inhibited trimethylolethane solutions Download PDF

Info

Publication number
US4709104A
US4709104A US06/787,621 US78762185A US4709104A US 4709104 A US4709104 A US 4709104A US 78762185 A US78762185 A US 78762185A US 4709104 A US4709104 A US 4709104A
Authority
US
United States
Prior art keywords
crystallization
trimethylolethane
propanol
solutions
solution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US06/787,621
Inventor
Paul E. Eckler
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
QUESTRA CHEMICALS CORP A GA CORP
Original Assignee
International Minerals and Chemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Minerals and Chemical Corp filed Critical International Minerals and Chemical Corp
Priority to US06/787,621 priority Critical patent/US4709104A/en
Assigned to INTERNATIONAL MINERALS & CHEMICAL CORPORATION, A CORP. OF NEW YORK reassignment INTERNATIONAL MINERALS & CHEMICAL CORPORATION, A CORP. OF NEW YORK ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ECKLER, PAUL E.
Priority to US07/083,177 priority patent/US4847439A/en
Application granted granted Critical
Publication of US4709104A publication Critical patent/US4709104A/en
Assigned to QUESTRA CHEMICALS CORP., A GA CORP. reassignment QUESTRA CHEMICALS CORP., A GA CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: INTERNATIONAL MINERALS & CHEMICAL CORPORATION
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
    • C07C29/94—Use of additives, e.g. for stabilisation

Definitions

  • This invention relates to a method for inhibiting crystallization of trimethylolethane from supersaturated aqueous solutions thereof and to the crystallization-inhibited solutions prepared in accordance with that method.
  • Liquids can be handled economically in bulk by pumping and metering, thus avoiding the manual labor associated with transporting and opening solid-containing containers and weighing solid charges.
  • Trimethylolethane is a water soluble crystalline polyhydric alcohol which finds widespread use in the chemical industry particularly in the manufacture of alkyd resins, drying oils and plasticizers.
  • Trimethylolethane (TME) while a crystalline solid in pure form, is for the above reasons advantageously shipped in bulk for commercial usage as its aqueous solutions.
  • Aqueous solutions of TME as concentrated as 80% solids can be shipped as heated solutions in insulated tank trucks.
  • Aqueous solutions of trimethylolethane at 50% solids can be shipped (as solutions) so long as the outdoor temperatures do not drop below 0°-5° C.
  • the solubility profile of TME in water is such that any cooling of concentrated aqueous TME solutions can easily result in solution supersaturation and concomitant crystallization of TME from solution. Indeed, supersaturated solutions of TME can "crystallize" into a solid crystalline mass. Cooling of concentrated aqueous TME solutions in shipment, in storage tanks and in pumping and metering equipment can result in a plant manager's nightmare. There is little that can be done with the resulting solid crystalline mass once it forms in shipping containers or processing equipment except to find some way to heat the "mass" to again form a high solids aqueous TME solution, or to remove the crystallized material mechanically from the crystal-clogged equipment.
  • crystallization is more of an art than a science. Processes based on crystallization steps can be difficult to operate consistently. In some cases crystallizations which have been practiced commercially for extended periods of time can, without warning or explanation, encounter difficulties with recovered yields and with crystallization rates. These effects are probably due to trace impurities which inhibit the crystallization process. Generally little is known about these inhibitors but it is logical that the inhibitors somehow interfere with the crystallization process. Often crystallization inhibitors are found by accident and they are nearly always specific to each solid/solvent system. In the case of pentaerythritol, a close cousin of trimethylolethane, some crystallization inhibitors have been identified, including formaldehyde, sucrose, caustic and trimethylolethane itself.
  • the present invention is based on applicant's investigation of crystallization inhibitors for supersaturated aqueous trimethylolethane solutions.
  • the following materials were found to be most active as crystallization inhibitors for supersaturated aqueous trimethylolethane solutions: methanol, isopropyl alcohol, 2-ethoxyethanol, 1-methoxy-2-propanol, formaldehyde (methanol inhibited), 1-dimethylamino-2-propanol, and formic acid.
  • methanol isopropyl alcohol
  • 2-ethoxyethanol 1-methoxy-2-propanol
  • formaldehyde methanol inhibited
  • 1-dimethylamino-2-propanol 1-dimethylamino-2-propanol and formaldehyde appeared to provide the highest degree of crystallization inhibition.
  • a method for inhibiting crystallization of trimethylolethane from supersaturated aqueous solutions thereof comprises forming the supersaturated solution in the presence of a crystallization inhibitor compound selected from the group consisting of methanol, formaldehyde, isopropyl alcohol, 2-ethoxyethanol, 1-methoxy-2-propanol, and 1-dimethylamino-2-propanol in an amount effective to inhibit trimethylolethane crystal formation.
  • the crystallization inhibitor preferably forms between about 5 and about 15%, more preferably about 10 to about 15% of the resulting supersaturated aqueous trimethylolethane solution.
  • crystallization inhibitors were identified experimentally by measuring the time needed for solidification on cooling of a 40% aqueous trimethylolethane solution in a freezer at 5° F.
  • Test solutions at the 5% additive level were prepared by combining 2.5 grams of additive with 47.5 grams of a stock solution of 400 grams of trimethylolethane dissolved in 360 ml water. At the 10% level, 5 grams of test additive was combined with 45 grams of a stock solution of 352 grams of trimethylolethane dissolved in 440 ml water. Crystallization inhibitors were identified by those test solutions which failed to solidify after two hours in a freezer at 5° F.
  • crystallization inhibitors identified in accordance with the present invention are not well understood. However, they probably function as kinetic crystallization inhibitors. Based on available data the crystallization inhibitors identified are not good solvents for trimethylolethane relative to water. Interestingly a number of compounds closely related to those found having crystallization inhibitory activity were tested but found inactive. Among compounds showing no crystallization inhibitory activity are ethanol, n-butanol, isobutyl alcohol, 2-butoxyethanol, diethylene glycol monoethyl ether, Dowanol DPM (dipropylene glycol monomethyl ether) ethylene glycol, propylene glycol, and 1,3- and 1,4-butane diols. While it is believed that some form of hydrogen bonding process may be involved in trimethylolethane crystallization inhibition, the mechanism by which the process occurs is not known.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

Crystallization of trimethylolethane from supersaturated aqueous solutions is inhibited in the presence of effective amounts of crystallization inhibitors selected from methanol, isopropanol, s-butyl alcohol, t-butyl alcohol, 2-ethoxyethanol, 2-methoxyethanol, 1-methoxy-2-propanol, formic acid and 1-dimethylamino-2-propanol.

Description

BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to a method for inhibiting crystallization of trimethylolethane from supersaturated aqueous solutions thereof and to the crystallization-inhibited solutions prepared in accordance with that method.
Most commercial customers for industrial chemicals prefer to handle bulk raw materials in liquid form. Liquids can be handled economically in bulk by pumping and metering, thus avoiding the manual labor associated with transporting and opening solid-containing containers and weighing solid charges.
Trimethylolethane is a water soluble crystalline polyhydric alcohol which finds widespread use in the chemical industry particularly in the manufacture of alkyd resins, drying oils and plasticizers. Trimethylolethane (TME), while a crystalline solid in pure form, is for the above reasons advantageously shipped in bulk for commercial usage as its aqueous solutions. Of course, the more concentrated solutions can be made, the more cost efficient shipping and handling can be. Aqueous solutions of TME as concentrated as 80% solids can be shipped as heated solutions in insulated tank trucks. Aqueous solutions of trimethylolethane at 50% solids can be shipped (as solutions) so long as the outdoor temperatures do not drop below 0°-5° C.
The solubility profile of TME in water is such that any cooling of concentrated aqueous TME solutions can easily result in solution supersaturation and concomitant crystallization of TME from solution. Indeed, supersaturated solutions of TME can "crystallize" into a solid crystalline mass. Cooling of concentrated aqueous TME solutions in shipment, in storage tanks and in pumping and metering equipment can result in a plant manager's nightmare. There is little that can be done with the resulting solid crystalline mass once it forms in shipping containers or processing equipment except to find some way to heat the "mass" to again form a high solids aqueous TME solution, or to remove the crystallized material mechanically from the crystal-clogged equipment.
It is therefore an object of this invention to provide a method for inhibiting crystallization in supersaturated aqueous solutions of trimethylolethane.
It is a further object of this invention to provide crystallization-inhibited aqueous trimethylolethane solutions and a method for preparing those crystallization-inhibited solutions.
It is still a further object of this invention to identify materials useful as stabilizers for aqueous trimethylolethane solutions, and to provide a liquid, pumpable grade of aqueous high solids trimethylolethane solution exhibiting resistance to unwanted, premature crystallization of trimethylolethane from solution.
DETAILED DESCRIPTION OF THE INVENTION
In many respects, crystallization is more of an art than a science. Processes based on crystallization steps can be difficult to operate consistently. In some cases crystallizations which have been practiced commercially for extended periods of time can, without warning or explanation, encounter difficulties with recovered yields and with crystallization rates. These effects are probably due to trace impurities which inhibit the crystallization process. Generally little is known about these inhibitors but it is logical that the inhibitors somehow interfere with the crystallization process. Often crystallization inhibitors are found by accident and they are nearly always specific to each solid/solvent system. In the case of pentaerythritol, a close cousin of trimethylolethane, some crystallization inhibitors have been identified, including formaldehyde, sucrose, caustic and trimethylolethane itself.
The present invention is based on applicant's investigation of crystallization inhibitors for supersaturated aqueous trimethylolethane solutions. Of the more than 100 chemical compositions evaluated the following materials were found to be most active as crystallization inhibitors for supersaturated aqueous trimethylolethane solutions: methanol, isopropyl alcohol, 2-ethoxyethanol, 1-methoxy-2-propanol, formaldehyde (methanol inhibited), 1-dimethylamino-2-propanol, and formic acid. Of these compounds 1-dimethylamino-2-propanol and formaldehyde appeared to provide the highest degree of crystallization inhibition.
Thus in accordance with the present invention a method is provided for inhibiting crystallization of trimethylolethane from supersaturated aqueous solutions thereof. The method comprises forming the supersaturated solution in the presence of a crystallization inhibitor compound selected from the group consisting of methanol, formaldehyde, isopropyl alcohol, 2-ethoxyethanol, 1-methoxy-2-propanol, and 1-dimethylamino-2-propanol in an amount effective to inhibit trimethylolethane crystal formation. The crystallization inhibitor preferably forms between about 5 and about 15%, more preferably about 10 to about 15% of the resulting supersaturated aqueous trimethylolethane solution.
The above-identified crystallization inhibitors were identified experimentally by measuring the time needed for solidification on cooling of a 40% aqueous trimethylolethane solution in a freezer at 5° F. Test solutions at the 5% additive level were prepared by combining 2.5 grams of additive with 47.5 grams of a stock solution of 400 grams of trimethylolethane dissolved in 360 ml water. At the 10% level, 5 grams of test additive was combined with 45 grams of a stock solution of 352 grams of trimethylolethane dissolved in 440 ml water. Crystallization inhibitors were identified by those test solutions which failed to solidify after two hours in a freezer at 5° F. Formic acid (88%), 1-dimethylamino-2-propanol (DMA-2P) and formaldehyde (37% aqueous) wholly or partially prevented crystallization in the supersaturated trimethylolethane solution at the 5% level. Compounds found to be effective crystallization inhibitors at the 10% level were methanol, formic acid, 1-dimethylamino-2-propanol, formaldehyde (37%), isopropyl alcohol, 2-ethoxyethanol and 1-methoxy-2-propanol (Dowanol PM). Secondary-butyl alcohol, tertiary-butyl alcohol and 2-methoxyethanol were found to exhibit partial efficacy as a crystallization inhibitor of TME solutions at the 10% by weight level.
The mode of action of the crystallization inhibitors identified in accordance with the present invention is not well understood. However, they probably function as kinetic crystallization inhibitors. Based on available data the crystallization inhibitors identified are not good solvents for trimethylolethane relative to water. Interestingly a number of compounds closely related to those found having crystallization inhibitory activity were tested but found inactive. Among compounds showing no crystallization inhibitory activity are ethanol, n-butanol, isobutyl alcohol, 2-butoxyethanol, diethylene glycol monoethyl ether, Dowanol DPM (dipropylene glycol monomethyl ether) ethylene glycol, propylene glycol, and 1,3- and 1,4-butane diols. While it is believed that some form of hydrogen bonding process may be involved in trimethylolethane crystallization inhibition, the mechanism by which the process occurs is not known.
It should be pointed out that the effective crystallization inhibiting additives described herein do not totally prevent crystallization at all levels of supersaturation. The efficacy of the inhibitors is measured essentially in terms of delaying crystallization. Even with the most effective additives, TME crystallization could be effected at low temperatures (high supersaturation levels) with seeding. Nonetheless, identification of crystallization inhibitors in accordance with the present invention offers a significant advantage for commercial manufacture and shipment of easily handled TME in bulk liquid form.

Claims (7)

I claim:
1. A method for inhibiting crystallization of trimethylolethane in a supersaturated aqueous solution thereof comprising forming said supersaturated solution in the presence of a crystallization inhibitor compound selected from the group consisting of isopropanol, s-butyl alcohol, t-butyl alcohol, 1-ethoxyethanol, 2-methoxyethanol, 1-methoxy-2-propanol, and 1-dimethylamino-2-propanol in an amount of from about 5% to about 15% by weight of the resulting solution.
2. The method of claim 1 wherein the crystallization-inhibitor forms about 10 percent by weight of the resulting crystallization inhibited supersaturated aqueous trimethylolethane solution.
3. The method of claim 1 wherein the crystallization-inhibitor compound is 1-dimethylamino-2-propanol.
4. The method of claim 3 wherein the crystallization-inhibitor compound forms about 5 percent by weight of the crystallization-inhibited supersaturated trimethylolethane solution.
5. A supersaturated aqueous solution of trimethylolethane containing about 5 to about 15 percent by weight of a crystallization-inhibitor compound selected from the group consisting of 2-ethoxyethanol, 1-methoxy-2-propanol, and 1-dimethylamino-2-propanol.
6. The trimethylolethane solution of claim 5 wherein the crystallization-inhibitor compound forms about 10 to about 15 percent by weight of the supersaturated aqueous solution.
7. The method of claim 1 wherein the crystallization-inhibitor compound is isopropyl alcohol.
US06/787,621 1985-10-15 1985-10-15 Crystallization-inhibited trimethylolethane solutions Expired - Fee Related US4709104A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US06/787,621 US4709104A (en) 1985-10-15 1985-10-15 Crystallization-inhibited trimethylolethane solutions
US07/083,177 US4847439A (en) 1985-10-15 1987-08-10 Crystallization-inhibited trimethylolethane solutions

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/787,621 US4709104A (en) 1985-10-15 1985-10-15 Crystallization-inhibited trimethylolethane solutions

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US07/083,177 Continuation-In-Part US4847439A (en) 1985-10-15 1987-08-10 Crystallization-inhibited trimethylolethane solutions

Publications (1)

Publication Number Publication Date
US4709104A true US4709104A (en) 1987-11-24

Family

ID=25142060

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/787,621 Expired - Fee Related US4709104A (en) 1985-10-15 1985-10-15 Crystallization-inhibited trimethylolethane solutions

Country Status (1)

Country Link
US (1) US4709104A (en)

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2270839A (en) * 1940-09-04 1942-01-20 Trojan Powder Co Purification of pentaerythritol
US2292926A (en) * 1938-05-10 1942-08-11 Du Pont Preparation of methyltrimethylolmethane
US2304985A (en) * 1941-02-14 1942-12-15 Trojan Powder Co Purification of trimethylol-methyl-methane
US2400724A (en) * 1942-10-28 1946-05-21 Du Pont Preparation of polyhydroxy compounds
US2420496A (en) * 1943-12-02 1947-05-13 Heyden Chemical Corp Recovery of products from aldehyde condensations
US2671118A (en) * 1951-08-25 1954-03-02 Trojan Powder Co Crystallization of trimethylol ethane
US2790837A (en) * 1954-06-08 1957-04-30 Celanese Corp Continuous production of trimethylolethane
GB808878A (en) * 1956-06-29 1959-02-11 Degussa Process for the production of methyl trimethylol methane
US3076854A (en) * 1955-12-05 1963-02-05 Heyden Newport Chemical Corp Recovery of trimethylolpropane
US3097245A (en) * 1959-01-13 1963-07-09 Trojan Powder Co Process for the preparation of trimethylolalkane

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2292926A (en) * 1938-05-10 1942-08-11 Du Pont Preparation of methyltrimethylolmethane
US2270839A (en) * 1940-09-04 1942-01-20 Trojan Powder Co Purification of pentaerythritol
US2304985A (en) * 1941-02-14 1942-12-15 Trojan Powder Co Purification of trimethylol-methyl-methane
US2400724A (en) * 1942-10-28 1946-05-21 Du Pont Preparation of polyhydroxy compounds
US2420496A (en) * 1943-12-02 1947-05-13 Heyden Chemical Corp Recovery of products from aldehyde condensations
US2671118A (en) * 1951-08-25 1954-03-02 Trojan Powder Co Crystallization of trimethylol ethane
US2790837A (en) * 1954-06-08 1957-04-30 Celanese Corp Continuous production of trimethylolethane
US3076854A (en) * 1955-12-05 1963-02-05 Heyden Newport Chemical Corp Recovery of trimethylolpropane
GB808878A (en) * 1956-06-29 1959-02-11 Degussa Process for the production of methyl trimethylol methane
US3097245A (en) * 1959-01-13 1963-07-09 Trojan Powder Co Process for the preparation of trimethylolalkane

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
Addadi et al., "Angen. Chem.", Int. Ed. Engl., 24, (1984), pp. 466-485.
Addadi et al., Angen. Chem. , Int. Ed. Engl., 24, (1984), pp. 466 485. *
Clatworthy et al., "J. Appl. Chem. Biotechnol", 26, (1976), pp. 30-36.
Clatworthy et al., J. Appl. Chem. Biotechnol , 26, (1976), pp. 30 36. *
Rogers et al., "J. Appl. Chem. Biotechnol", 24, (1974), pp. 171-180.
Rogers et al., J. Appl. Chem. Biotechnol , 24, (1974), pp. 171 180. *

Similar Documents

Publication Publication Date Title
US4282007A (en) Novel fuel composition containing alcohol
FI61786B (en) BIOCID LOESNING INNEHAOLLANDE ETT ALKALIMETALLSALT AV 1,2-BENZISOTIAZOLIN-3-ON
AU2007264228A1 (en) Solvent system for the preparation of N-alkyl thiophosphoric triamide solutions, composition containing N-alkyl thiophosphoric triamide and the use thereof
US4282008A (en) Novel fuel composition containing alcohol
CA2070551C (en) Polymerization inhibitors for acrylic acids and esters
US4709104A (en) Crystallization-inhibited trimethylolethane solutions
JP2004517209A (en) Aqueous coolant for test run phase with vapor space corrosion inhibitor
US4847439A (en) Crystallization-inhibited trimethylolethane solutions
US4192686A (en) Compositions and method for inhibiting formation of explosive compounds and conditions in silvering concentrates for electroless deposition of silver
US4401624A (en) Buffered solutions which have a reduced corrosive nature
US4778654A (en) Alkylaniline/formaldehyde co-oligomers as corrosion inhibitors
US5376159A (en) Corrosion inhibitor for nitrogen fertilizer solutions
US4126664A (en) Stabilized cyanamide solutions
US4556536A (en) Method and composition for corrosion inhibition of carbon steel by ammonium sulfate
US4505717A (en) Corrosion inhibited motor fuel
JP4278205B2 (en) Compositions of aliphatic alkanals and methods for improving the storage stability of the compounds
US3152187A (en) Condensation product of unsaturated diols and polyalkylene polyamines and method of preparation thereof
US4475939A (en) Stabilized fertilizer solutions
AU745800B2 (en) Method of stabilizing aldehydes
US2077469A (en) The packing and transportation of ammonium nitrate-ammonia compositions
US4435603A (en) Method for preventing caking of polyols
EP1125919B2 (en) Stabilized hydroxyalkyl(meth)acrylate
US2742492A (en) Nitrate formulations
US3029139A (en) Inhibition of corrosive action of aqueous ammonium nitrate-urea on ferrous metals
US2772148A (en) Fuel compositions

Legal Events

Date Code Title Description
AS Assignment

Owner name: INTERNATIONAL MINERALS & CHEMICAL CORPORATION, A C

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:ECKLER, PAUL E.;REEL/FRAME:004477/0062

Effective date: 19851002

AS Assignment

Owner name: QUESTRA CHEMICALS CORP., A GA CORP.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:INTERNATIONAL MINERALS & CHEMICAL CORPORATION;REEL/FRAME:005108/0203

Effective date: 19890331

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
FP Lapsed due to failure to pay maintenance fee

Effective date: 19911124

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362